It certainly looked like the Buffalo Bills could be the best team in the NFL at the midway point of this season. They destroyed the Miami Dolphins and Houston Texans by a combined score of 75-0. They beat the Kansas City Chiefs handily. They lost to the Tennessee Titans, but only by a field goal. They looked very strong.
Then the Bills went out in Week 9 and lost to the Jacksonville Jaguars, a team that is currently 2-10. That game looked terrible, but the following week the Bills had another dominating win, 45-17 over the Jets. Then the Colts ran all over them in a dominating 41-15 victory. The Bills looked down again until they came back and dominated the Saints 31-6 the next week.
The constant roller coaster from week-to-week has us wondering: Who are these Buffalo Bills, anyway? Are they the really great team that easily beat the Chiefs? Or the mediocre team that couldn't even beat the Jaguars? The answer is that they are both. Overall, the Bills are pretty good, but more importantly they are inconsistent.
In fact, the Bills may be the most inconsistent team in the NFL since at least 1983.
Football Outsiders measures inconsistency using a stat called variance (explained here). Instead of looking at raw scores, the DVOA ratings break down every play and compare success to a league average adjusted for situation and opponent. These ratings filter out some of the effects of luck and can tell that a 9-7 loss to Tampa Bay was probably a good game while a 9-7 loss to Jacksonville was definitely not.
Variance looks at the DVOA for each individual game and determines just how consistent or inconsistent a team has been that season. And with a current variance of 44.5%, the 2021 Bills come out as the most inconsistent team we've ever tracked in stats that go back to 1983. For comparison, the median variance for an NFL team over a 16-game season is 14.6%.
Below we'll look at the five most inconsistent teams as well as the five most inconsistent teams that made the playoffs and the most inconsistent Super Bowl champion since 1983. After all, the Bills could definitely find themselves with that title by the end of this season.